Argonne researchers have developed a unique application of technology that involves using metal oxide semiconductor nanoparticles to target and control biological molecules. This approach promises to fuel medical breakthroughs in many areas, including the treatment of disease, in vivo gene surgery, and cellular drug delivery.

Description

Scientists at Argonne National Laboratory, led by Tijana Rajh, have developed novel nanometer-sized metal oxide semiconductors that allow researchers to target, initiate, and control in vitro and in vivo chemical reactions in biological molecules, such as DNA, proteins, and antibodies. Rajh and her team devised a technique that chemically links biomolecules to specially designed inorganic nanoparticles. The unique inorganic-biomolecule interface acts as a “conductive wire” that initiates chemical changes in the linked biomolecule and any complexes it may have formed with other biological macromolecules.

To demonstrate this technique, the team synthesized modified nanoparticles of the metal oxide semiconductor titanium dioxide (TiO2) and linked them to a variety of biological molecules to produce a stable inorganic-biomolecule composite. The ability to create such a stable composite is important: it imparts stability and a high degree of specificity to the nanoparticles, allowing them to target and bind to many biological molecules, including DNA, RNA, proteins, and various receptors on a cell’s surface.

Once the nanoparticle has bound to its selected biological target, light is used to form a complex charge separation in the TiO2 semiconductor. A chemical reaction is then initiated by transferring electrons between the inorganic and biological sides of the nanoparticle through the conductive wire. This reaction alters the structural and thermodynamic properties of the composite, affecting its function.

Benefits

The ability to electronically link titanium dioxide particles with DNA and other biological molecules has opened the door to an array of promising medical innovations. The hybrid nanoparticles have several potential commercial applications relating to their controllable dual “locate and destroy” function, including acting as synthetic DNA/RNA endonucleases.

Research has also uncovered the ability of these nanoparticles to target structures within a cell—a finding that could represent a ground-breaking tool for spatially and temporally controlled in vivo gene surgery and targeted cell metabolic intervention. Another intriguing application involves using the light-activated chemistries of the hybrid nanoparticles to prevent, control, and cure a variety of diseases.